How to Deal with De-Motivation?

You're lv41 and already de-motivated?

Just quit.

I'd be de-motivated too if 3 of my characters were stolen.

Not much I can do about the stolen part except tell you to be more careful and read up on it. Report it and pray something happens, though nothing ever does.

And as for training, do whatever feels right. I would pq and train non-stop early on and then eventually I'd hit a wall where I just didn't want to go further. I think it was once at 53 (After getting there in a little over a week.) and... 75? And now I'm at 112 for my cb, but now play my bishop in the hopes of making money.
In other words, don't force yourself, race or not. If you do race for it, go in small steps.

Save all quests that aren't level or time limited till later. Once I hit a high level and was bored of grinding, I was out of quests to do, and thus was bored. Maybe go hpq some. I've seen some people go play there when bored. You could also try farming an item, but sometimes trying to find a specific scroll can be harder than training.

However, never train or hunt in an area with no safe spot. Places like himes makes it hard to talk, and even if you can, stressful to do so. It can ruin all fun of grinding or farming.

Or you could wait and just hang out, and wait until Nexon gets it together and makes it less impossible to do things without nx.